K1 88-Tank


The K1 is a South Korean main battle tank in use with the Republic of Korea Armed Forces, developed by Hyundai Precision. The vehicle's early design work was based on General Dynamics' M1 Abrams, with some noticeable differences including a combined system of hydropneumatic suspension and torsion bars, and a river-crossing fording kit, to meet the required operational capability that was specific to combat operations in the mountainous and swampy terrain of the Korean Peninsula. The K1A1 entered service in 1999, upgraded with a 120 mm smoothbore gun, and outfitted with more modern electronics, ballistic computers, and fire control systems developed by Samsung Electronics. Hyundai Rotem produced 1,511 K1 and K1A1 tanks between 1985 and 2010.

History and overview

In the 1970s, South Korea was desperately in need of additional main battle tanks. The M4A3E8 "Easy Eight" variant of Sherman tanks, dating back to World War II, had been retired from service by the South Korean army, and the backbone of the South Korean armor was formed up of M47 and M48 Patton tanks. Meanwhile, North Korea had both numerical and technological advantages over the South Korean armor with their T-62 main battle tanks.
At first, attempts were made to obtain the United States' M60A1 Pattons, but they ended in failure. It was deemed that, even if the M60A1s were obtainable, there would not be enough of them to give the South Korean forces a significant advantage over existing North Korean tanks. A number of other plans were also devised, such as upgrading the existing M48 Pattons to the M48A3 and A5 standard, as well as obtaining the license to domestically produce Germany's Leopard 1 main battle tank. Only the upgrades to the Pattons were carried out, with the results being the M48A3K and M48A5K, while producing Leopard 1s was deemed counterproductive, as a newer generation of main battle tanks were already being developed and tested in both the U.S. and Germany, namely the M1 Abrams and Leopard 2.
In light of this, the Park Chung-hee administration announced plans to domestically produce main battle tanks that were comparable to the newer generation of main battle tanks. However, having no experience in the design, development and manufacture of main battle tanks to speak of, the task assigned to the South Korean industry was all but impossible. Upon realization of this, foreign designs were considered and evaluated, on condition that the winning design be licensed and produced domestically. The winning design was based on the XM1, the prototype of M1 Abrams, by Chrysler Defense, the company which was later sold to General Dynamics and renamed General Dynamics Land Systems. Soon afterwards, South Korean officials were dispatched to General Dynamics Land Systems for supervision of the design, which would spawn the XK1.
With its design being based on XM1, the XK1 shared various similarities with it. However, upon closer inspection, numerous differences can be found. The differences included the weight, height, engine, transmission, and several other components used in the vehicles.
The XK1 retained the XM1's M68E1 105 mm rifled main gun, which would also be domestically produced under license with the designation KM68, as well as a fire control system by Hughes Aircraft Company and the rangefinder. One of the major differences was the addition of tank commander's independent panoramic sights on the XK1, which was missing on XM1, giving the XK1 the capability to utilize the FCS more effectively, notably by engaging in hunter-killer tactics, which the M1 series could not do until the introduction of the M1A2. The tank commander's panoramic sights were not, however, equipped with light amplification or thermal optics, which led to the tank commander having to rely on personal night vision goggles to operate his sights, while the gunner's sights were equipped with a thermal observation device, which meant that the XK1 had superior sensors until the introduction of the M1A2.
XK1 tanks are also equipped with a hybrid suspension system consisting of hydropneumatic system on road wheels 1, 2 and 6, while 3, 4 and 5 are equipped with torsion bars, a feature not present on the XM1, granting the XK1 greater stability and ability to elevate and depress the main gun nearly twice as much as tanks equipped with torsion bars alone.
The development of the vehicle was completed in 1983, with a prototype being delivered to the South Korean government in the same year. As mentioned above, however, the AVCR-1790 used for the design was replaced by MTU MB Ka-501 just prior to mass production, which resulted in the K1's engine deck and exhaust grilles becoming cosmetically similar to the Leopard 2's. And officially, in 1984, the development of Korean K1 tanks was completed. For reference, K1 tanks and K1A1 tanks developed in 1997 were mentioned in the history of Hyundai Rotem.
Hyundai Precision, now known as Hyundai Rotem, took responsibility for manufacturing the tanks, and the mass production began in 1985, with deployment lasting until 1987. The vehicle was not, however, unveiled until 1987 for security purposes. Foreign journalists were invited to the unveiling ceremony, and a massive training exercise using the new tanks took place during the event for publicity.
After the production of approximately 450 K1s, the Gunner's Primary Sights designed by Hughes was replaced by the Gunner's Primary Tank Thermal Sights by Texas Instruments. The new system also replaced the Nd:YAG laser rangefinder used in the Hughes unit with a CO2-based one, which has proven to be safer to the users' eyes, although having less effective range than the former in foul weather.
While the exact composition of the armor has still not been released, it has been confirmed that K1 is equipped with composite armor similar to Chobham. Initial production of K1-88 had 400 to 500mm thick frontal armor, later it was increased up to 600mm. The vehicle is also equipped with an automatic fire extinguishing system. The engine compartment detector is thermocouple wire, and the crew compartment detector is an optical sensor. The extinguishant used is Halon1301, commonly used by western main battle tanks. While the air conditioning system is installed to aid in crew comfort, the vehicle lacks an overpressure system for CBRN defense, and is not protected from chemical, biological, radiological and nuclear attacks, requiring the crew to don protective gear while operating in a contaminated environment.
Production remained at approximately 100 units per year at its peak.
On 6 August 2010, during a live firing exercise at Paju, a round exploded in the barrel of a K1's 105 mm gun, destroying the gun, but leaving crew uninjured. This was reported to be the latest in a series of such accidents since the K1 entered service.

Development of K1A1

The K1A1, an upgraded version of the K1 MBT, was accepted into Korean service on 13 October 2001, after the first one was produced on 3 April 1996. The KM68 main gun has been replaced with the KM256 120 mm main gun which nearly doubled the penetration power of the original vehicle. In addition, its fire control system, thermal sights, LASER rangefinder, turret and gun stabilization and armor have been improved, giving the vehicle greater survivability and lethality. The improved armor is called 'Korean Special Armour Plate '. The weight of the vehicle has increased along with the upgrade, and has slightly lowered its power-to-weight ratio and speed, the former of which was considered already too low for the rough Korean terrain by some critics.
The KCPS specifications for K1A1 is as follows;
The carbon dioxide laser rangefinder's specification is as follows;
The K1A1 can easily be distinguished from the K1 by the shape of the gun, location of the co-axial machinegun, shape of the commander's panoramic sight, and overall angular shape of the turret. The 120 mm smoothbore gun of K1A1 is thicker than the K1's 105 mm rifled gun and has a thicker thermal sleeve a third of the way from the base of the gun. The co-axial machinegun on K1A1 is located at a much higher point compared to the K1. The K1A1 also features a somewhat cone-shaped day/night KGPS compared to day-only sight of the K1, which has a plain, tube-like appearance to it.
The ROK Army intends to standardize its K1 fleet by procuring 700 new-production K1A1 tanks while upgrading some 1,000 older-model K1s to the K1A1 configuration.

Variants and upgrades

; 1,027 K1/E1 and 484 K1A1/A2
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